Merge "Support to close two TaskFragments in predict back animation" into main

2 files changed, 176 insertions, 30 deletions

diff --git a/services/core/java/com/android/server/wm/BackNavigationController.java b/services/core/java/com/android/server/wm/BackNavigationController.java
index be7b8559e39e..c5902c965b43 100644
--- a/services/core/java/com/android/server/wm/BackNavigationController.java
+++ b/services/core/java/com/android/server/wm/BackNavigationController.java
@@ -395,7 +395,8 @@ class BackNavigationController {
      *
      * @return false if unable to predict what will happen
      */
-    private static boolean getAnimatablePrevActivities(@NonNull Task currentTask,
+    @VisibleForTesting
+    static boolean getAnimatablePrevActivities(@NonNull Task currentTask,
             @NonNull ActivityRecord currentActivity,
             @NonNull ArrayList<ActivityRecord> outPrevActivities) {
         if (currentActivity.mAtmService
@@ -413,45 +414,86 @@ class BackNavigationController {
         // Searching previous
         final ActivityRecord prevActivity = currentTask.getActivity((below) -> !below.finishing,
                 currentActivity, false /*includeBoundary*/, true /*traverseTopToBottom*/);
-        if (prevActivity == null) {
-            // No previous activity in this task, can still predict if previous task exists.
-            return true;
-        }
-        if (currentTask.getActivity((above) -> !above.finishing, currentActivity,
-                false /*includeBoundary*/, false /*traverseTopToBottom*/) != null) {
-            // another activity is above this activity, don't know what will happen
-            return false;
-        }
 
         final TaskFragment currTF = currentActivity.getTaskFragment();
-        final TaskFragment prevTF = prevActivity.getTaskFragment();
-        if (currTF != prevTF && prevTF != null) {
-            final TaskFragment prevTFAdjacent = prevTF.getAdjacentTaskFragment();
-            if (prevTFAdjacent != null) {
-                if (prevTFAdjacent == currTF) {
-                    outPrevActivities.clear();
-                    // No more activity in task, so it can predict if previous task exists.
-                    // Otherwise, unable to predict what will happen when app receive
-                    // back key, skip animation.
-                    return currentTask.getActivity((below) -> !below.finishing, prevActivity,
+        if (currTF != null && currTF.asTask() == null) {
+            // The currentActivity is embedded, search for the candidate previous activities.
+            if (prevActivity != null && currTF.hasChild(prevActivity)) {
+                // PrevActivity is under the same task fragment, that's it.
+                outPrevActivities.add(prevActivity);
+                return true;
+            }
+            if (currTF.getAdjacentTaskFragment() != null) {
+                // The two TFs are adjacent (visually displayed side-by-side), search if any
+                // activity below the lowest one
+                // If companion, those two TF will be closed together.
+                if (currTF.getCompanionTaskFragment() != null) {
+                    final WindowContainer commonParent = currTF.getParent();
+                    final TaskFragment adjacentTF = currTF.getAdjacentTaskFragment();
+                    final TaskFragment lowerTF = commonParent.mChildren.indexOf(currTF)
+                            < commonParent.mChildren.indexOf(adjacentTF)
+                            ? currTF : adjacentTF;
+                    final ActivityRecord lowerActivity = lowerTF.getTopNonFinishingActivity();
+                    // TODO (b/274997067) close currTF + companionTF, open next activities if any.
+                    // Allow to predict next task if no more activity in task. Or return previous
+                    // activities for cross-activity animation.
+                    return currentTask.getActivity((below) -> !below.finishing, lowerActivity,
                             false /*includeBoundary*/, true /*traverseTopToBottom*/) == null;
-                } else {
-                    final ActivityRecord prevActivityAdjacent =
-                            prevTFAdjacent.getTopNonFinishingActivity();
-                    if (prevActivityAdjacent != null) {
-                        outPrevActivities.add(prevActivityAdjacent);
-                    } else {
-                        // Don't know what will happen.
-                        outPrevActivities.clear();
-                        return false;
-                    }
                 }
+                // Unable to predict if no companion, it can only close current activity and make
+                // prev Activity full screened.
+                return false;
+            } else if (currTF.getCompanionTaskFragment() != null) {
+                // TF is isStacked, search bottom activity from companion TF.
+                //
+                // Sample hierarchy: search for underPrevious if any.
+                //     Current TF
+                //     Companion TF (bottomActivityInCompanion)
+                //     Bottom Activity not inside companion TF (underPrevious)
+                final TaskFragment companionTF = currTF.getCompanionTaskFragment();
+                // find bottom activity in Companion TF.
+                final ActivityRecord bottomActivityInCompanion = companionTF.getActivity(
+                        (below) -> !below.finishing, false /* traverseTopToBottom */);
+                final ActivityRecord underPrevious = currentTask.getActivity(
+                        (below) -> !below.finishing, bottomActivityInCompanion,
+                        false /*includeBoundary*/, true /*traverseTopToBottom*/);
+                if (underPrevious != null) {
+                    outPrevActivities.add(underPrevious);
+                    addPreviousAdjacentActivityIfExist(underPrevious, outPrevActivities);
+                }
+                return true;
             }
         }
+
+        if (prevActivity == null) {
+            // No previous activity in this Task nor TaskFragment, it can still predict if previous
+            // task exists.
+            return true;
+        }
+        // Add possible adjacent activity if prevActivity is embedded
+        addPreviousAdjacentActivityIfExist(prevActivity, outPrevActivities);
         outPrevActivities.add(prevActivity);
         return true;
     }
 
+    private static void addPreviousAdjacentActivityIfExist(@NonNull ActivityRecord prevActivity,
+            @NonNull ArrayList<ActivityRecord> outPrevActivities) {
+        final TaskFragment prevTF = prevActivity.getTaskFragment();
+        if (prevTF == null || prevTF.asTask() != null) {
+            return;
+        }
+
+        final TaskFragment prevTFAdjacent = prevTF.getAdjacentTaskFragment();
+        if (prevTFAdjacent == null || prevTFAdjacent.asTask() != null) {
+            return;
+        }
+        final ActivityRecord prevActivityAdjacent =
+                prevTFAdjacent.getTopNonFinishingActivity();
+        if (prevActivityAdjacent != null) {
+            outPrevActivities.add(prevActivityAdjacent);
+        }
+    }
+
     private static void findAdjacentActivityIfExist(@NonNull ActivityRecord mainActivity,
             @NonNull ArrayList<ActivityRecord> outList) {
         final TaskFragment mainTF = mainActivity.getTaskFragment();
diff --git a/services/tests/wmtests/src/com/android/server/wm/BackNavigationControllerTests.java b/services/tests/wmtests/src/com/android/server/wm/BackNavigationControllerTests.java
index afea8114d508..4d4d397585b7 100644
--- a/services/tests/wmtests/src/com/android/server/wm/BackNavigationControllerTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/BackNavigationControllerTests.java
@@ -242,6 +242,110 @@ public class BackNavigationControllerTests extends WindowTestsBase {
     }
 
     @Test
+    public void backTypeCrossActivityInTaskFragment() {
+        final Task task = createTask(mDefaultDisplay);
+        final TaskFragment tf1 = createTaskFragmentWithActivity(task);
+        final TaskFragment tf2 = createTaskFragmentWithActivity(task);
+        final ArrayList<ActivityRecord> outPrevActivities = new ArrayList<>();
+
+        ActivityRecord prevAr = tf1.getTopMostActivity();
+        ActivityRecord topAr = tf2.getTopMostActivity();
+        boolean predictable;
+
+        // Stacked + no Companion => predict for previous activity.
+        // TF2
+        // TF1
+        predictable = BackNavigationController.getAnimatablePrevActivities(task, topAr,
+                outPrevActivities);
+        assertTrue(outPrevActivities.contains(prevAr));
+        assertTrue(predictable);
+        outPrevActivities.clear();
+
+        // Stacked + companion => predict for previous task
+        tf2.setCompanionTaskFragment(tf1);
+        predictable = BackNavigationController.getAnimatablePrevActivities(task, topAr,
+                outPrevActivities);
+        assertTrue(outPrevActivities.isEmpty());
+        assertTrue(predictable);
+        tf2.setCompanionTaskFragment(null);
+
+        // Adjacent + no companion => unable to predict
+        // TF1 | TF2
+        tf1.setAdjacentTaskFragment(tf2);
+        tf2.setAdjacentTaskFragment(tf1);
+        predictable = BackNavigationController.getAnimatablePrevActivities(task, topAr,
+                outPrevActivities);
+        assertTrue(outPrevActivities.isEmpty());
+        assertFalse(predictable);
+        predictable = BackNavigationController.getAnimatablePrevActivities(task, prevAr,
+                outPrevActivities);
+        assertTrue(outPrevActivities.isEmpty());
+        assertFalse(predictable);
+
+        // Adjacent + companion => predict for previous task
+        tf1.setCompanionTaskFragment(tf2);
+        tf2.setCompanionTaskFragment(tf1);
+        predictable = BackNavigationController.getAnimatablePrevActivities(task, topAr,
+                outPrevActivities);
+        assertTrue(outPrevActivities.isEmpty());
+        assertTrue(predictable);
+        predictable = BackNavigationController.getAnimatablePrevActivities(task, prevAr,
+                outPrevActivities);
+        assertTrue(outPrevActivities.isEmpty());
+        assertTrue(predictable);
+        // reset
+        tf1.setAdjacentTaskFragment(null);
+        tf2.setAdjacentTaskFragment(null);
+        tf1.setCompanionTaskFragment(null);
+        tf2.setCompanionTaskFragment(null);
+
+        final TaskFragment tf3 = new TaskFragmentBuilder(mAtm)
+                .createActivityCount(2)
+                .setParentTask(task)
+                .build();
+        topAr = tf3.getTopMostActivity();
+        prevAr = tf3.getBottomMostActivity();
+        // Stacked => predict for previous activity.
+        // TF3
+        // TF2
+        // TF1
+        predictable = BackNavigationController.getAnimatablePrevActivities(task, topAr,
+                outPrevActivities);
+        assertTrue(outPrevActivities.contains(prevAr));
+        assertTrue(predictable);
+        // reset
+        outPrevActivities.clear();
+
+        // Adjacent => predict for previous activity.
+        // TF2 | TF3
+        // TF1
+        tf2.setAdjacentTaskFragment(tf3);
+        tf3.setAdjacentTaskFragment(tf2);
+        predictable = BackNavigationController.getAnimatablePrevActivities(task, topAr,
+                outPrevActivities);
+        assertTrue(outPrevActivities.contains(prevAr));
+        assertTrue(predictable);
+        // reset
+        outPrevActivities.clear();
+        tf2.setAdjacentTaskFragment(null);
+        tf3.setAdjacentTaskFragment(null);
+
+        final TaskFragment tf4 = createTaskFragmentWithActivity(task);
+        // Stacked + companion => predict for previous activity below companion.
+        // Tf4
+        // TF3
+        // TF2
+        // TF1
+        tf4.setCompanionTaskFragment(tf3);
+        tf3.setCompanionTaskFragment(tf4);
+        topAr = tf4.getTopMostActivity();
+        predictable = BackNavigationController.getAnimatablePrevActivities(task, topAr,
+                outPrevActivities);
+        assertTrue(outPrevActivities.contains(tf2.getTopMostActivity()));
+        assertTrue(predictable);
+    }
+
+    @Test
     public void backTypeDialogCloseWhenBackFromDialog() {
         DialogCloseTestCase testCase = createTopTaskWithActivityAndDialog();
         IOnBackInvokedCallback callback = withSystemCallback(testCase.task);